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Summary Objectives The purpose of the present study was to establish the method for an acoustic simulation of a vocal tract created from CT data during phonation of the Japanese vowel /a/ and to verify the validity of the simulation. Material and methods The subjects were 15 healthy adults (8 males, 7 females). The vocal tract model was created from CT data acquired during sustained phonation of the Japanese vowel /a/. After conversion to a mesh model for analysis, a wave acoustic analysis was performed with a boundary element method. The wall and the bottom of the vocal tract model were regarded as a rigid wall and a nonrigid wall, respectively. The acoustic medium was set to 37°C, and a point sound source was set in the place corresponding to the vocal cord as a sound source. The first and second formant frequencies (F1 and F2) were calculated. For 1 of the 15 subjects, the range from the upper end of the frontal sinus to the tracheal bifurcation was scanned, and 2 models were created: model 1 included the range from the frontal sinus to the tracheal bifurcation; and model 2 included the range from the frontal sinus to the glottis and added a virtually extended trachea by 12 cm cylindrically. F1 and F2 calculated from models 1 and 2 were compared. To evaluate the validity of the present simulation, F1 and F2 calculated from the simulation were compared with those of the actual voice and the sound generated using a solid model and a whistle-type artificial larynx. To judge the validity, the vowel formant frequency discrimination threshold reported in the past was used as a criterion. Namely, the relative discrimination thresholds (%), dividing ▵F by F, where F was the formant frequency calculated from the simulation, and ▵F was the difference between F and the formant frequency of the actual voice and the sound generated using the solid model and artificial larynx, were obtained. Results F1 and F2 calculated from models 1 and 2 were similar. Therefore, to reduce the exposure dose, the remaining 14 subjects were scanned from the upper end of the frontal sinus to the glottis, and model 2 with the trachea extended by 12 cm virtually was used for the simulation. The averages of the relative discrimination thresholds against F1 and F2 calculated from the actual voice were 5.9% and 4.6%, respectively. The averages of the relative discrimination thresholds against F1 and F2 calculated from the sound generated by using the solid model and the artificial larynx were 4.1% and 3.7%, respectively. Conclusions The Japanese vowel /a/ could be simulated with high validity for the vocal tract models created from the CT data during phonation of /a/ using the boundary element method.

Aims. Total laryngectomy still plays an essential part in the treatment of laryngeal cancer and loss of voice is the most feared consequence of the surgery. Commonly used rehabilitation methods include esophageal voice, electrolarynx, and implantation of voice prosthesis. In this paper we focus on a new perspective of vocal rehabilitation utilizing alternative and augmentative communication (AAC) methods. Methods and Patients. 61 consecutive patients treated by means of total laryngectomy with or w/o voice prosthesis implantation were included in the study. All were offered voice banking and personalized speech synthesis (PSS). They had to voluntarily express their willingness to participate and to prove the ability to use modern electronic communication devices. Results. Of 30 patients fulfilling the study criteria, only 18 completed voice recording sufficient for voice reconstruction and synthesis. Eventually, only 7 patients started to use this AAC technology during the early postoperative period. The frequency and total usage time of the device gradually decreased. Currently, only 6 patients are active users of the technology. Conclusion. The influence of communication with the surrounding world on the quality of life of patients after total laryngectomy is unquestionable. The possibility of using the spoken word with the patient's personalized voice is an indisputable advantage. Such a form of voice rehabilitation should be offered to all patients who are deemed eligible.

Summary Aim Previous reports have demonstrated good outcomes with the use of the Anterolateral Thigh Flap (ALT) in pharyngeal reconstruction. We report a new modification of free ALT flap pharyngeal reconstruction utilizing vascularised fascial wings or extensions placed in the parastomal gutters to cover the major neck vessels. Patients and methods This was a single-centre retrospective case review. Between November 2017 and January 2019, 8 patients (6 male, 2 female mean age 61, range 35 to 74) underwent near circumferential pharyngeal reconstruction by the modified technique. 3 patients had laryngopharyngectomy for radiorecurrent larynx SCC, 2 for primary, advanced laryngeal SCC, and 3 for primary hypopharyngeal SCC. Results All eight patients regained adequate swallow to maintain nutrition without tube-feeding. Two of the patients have been assessed as appropriate for tracheo-esophageal puncture and are awaiting placement. One patient uses an electrolarynx for speech and 5 patients aphonic only. One patient died 2 months after the procedure from chest infection. There were no flap failures, no fistulas and no strictures at one year. One patient who underwent a salvage laryngopharyngectomy experienced parastomal wound dehiscence, but critically there was no return to theatre for exposed major vessels and the wound healed within 6 weeks requiring dressings only. Conclusion Here we report outcomes of pharyngeal reconstruction with a modified single perforator free ALT flap using fascial extensions to line the parastomal gutters. In the event of parastomal dehiscence, the placement of vascularized tissue parastomally may facilitate spontaneous healing and prevent major vessel exposure.

Purpose: Following a total laryngectomy in which the larynx is completely removed, individuals in the USA have three primary options for alaryngeal verbal communication including tracheoesophageal speech (TES), oesophageal speech (ES) and electrolarynx (EL). Using a large sample of participants from across the USA, this study investigated listener impressions of each primary type of alaryngeal communication. As these are the individuals more likely to be participating in social interactions and in positions of hiring for employment, the general public's impressions of TES, ES and EL may be a vital consideration during the treatment process.Method: A total of 381 individuals rated eight speech samples, including samples from speakers of each alaryngeal communication modality as well samples from age and sex matched laryngeal speakers, with regards to three outcome measures: intelligence, likability and employability.Result: Listener impressions of alaryngeal speech samples were modulated by the type of communication mode. Further, the patterns of results differed by speaker sex, with ES speech rated consistently more favourable for female speakers across all outcome measures and TES rated consistently more favourable for male speakers across all outcome measures.Conclusion: An overall preference for laryngeal speech was noted, particularly with male speakers. The female ES stimuli, interestingly, was the highest rated alaryngeal communication modality. Regardless of speaker sex, all alaryngeal modes greatly affected impressions of employability relative to impressions of likeability and intelligence.

OBJECTIVE Traditionally, after total laryngopharyngectomy (TLP), patients cannot speak without a prosthesis or an artificial larynx. In Taiwan, most patients use a commercialized pneumatic laryngeal device (PLD). Phonatory tube reconstruction with the anterolateral thigh (ALT) flap is a novel, modified version of synchronous digestive and phonatory reconstruction involving a free muscular cutaneous flap. This study reviewed and compared speech performance between patients who underwent novel flap reconstruction and conventional PLD users. METHOD We retrospectively reviewed patients with laryngeal or hypopharyngeal cancer who underwent TLP from August 2017 to September 2019. The voice handicap index (VHI), speech intelligibility, acoustic and aerodynamic analysis results, and speech range profile (SRP) were compared between patients who underwent ALT phonatory tube reconstruction (ALT group) and those using PLDs (PLD group). RESULTS Twenty patients were included; 13 patients were included in the ALT group, and 7 patients were included in the PLD group. Compared to the PLD group, the ALT group had a better fundamental frequency range (P

Purpose The aim of this study is to use functional magnetic resonance (fMRI) to analyse the cortical presentation of selected language functions in patients after a total laryngectomy. Methods Eighteen patients after total laryngectomy treated with electrolarynx speech and 18 volunteers were included. The mean number of patients’ post-operative speech rehabilitation sessions was five (range of 3–8 sessions). Four paradigms were used, including noun generation, pseudoword reading, reading phrases with pseudowords, and nonliteral sign reproduction. Results In noun, the most significant difference between the groups was the stronger activation of both lingual gyri in the volunteers. Pseudoword reading resulted in stronger activations in patients than in volunteers in the lingual gyri, the right cerebellum, the right Broca’s area, and the right parietal operculum. Reading phrases with pseudowords involved different parts of the Brodmann area 40. During nonliteral sign reproduction, there was a stronger activation of the left Broca’s area in volunteers and a stronger activation of the left premotor cortex in patients. Conclusion This study provides evidence of altered cortical activation in response to language tasks in patients after a laryngectomy compared with healthy volunteers, which may be considered brain plasticity in response to a laryngectomy.

Background The main modalities for voice restoration after laryngectomy are the electrolarynx, and the tracheoesophageal puncture [Correction added on 30 January 2020 after first online publication: The preceding sentence has been revised. It originally read "The main modalities for voice restoration after laryngectomy are the electrolarynx and the tracheoesophageal puncture."]. All have limitations and new technologies may offer innovative alternatives via silent speech. Objective To describe a novel and personalized method of voice restoration using machine learning applied to electromyographic signal from articulatory muscles for the recognition of silent speech in a patient with total laryngectomy. Methods Surface electromyographic (sEMG) signals of articulatory muscles were recorded from the face and neck of a patient with total laryngectomy who was articulating words silently. These sEMG signals were then used for automatic speech recognition via machine learning. Sensor placement was tailored to the patient's unique anatomy, following radiation and surgery. A personalized wearable mask covering the sensors was designed using 3D scanning and 3D printing. Results Using seven sEMG sensors on the patient's face and neck and two grounding electrodes, we recorded EMG data while he was mouthing "Tedd" and "Ed." With data from 75 utterances for each of these words, we discriminated the sEMG signal with 86.4% accuracy using an XGBoost machine-learning model. Conclusions This pilot study demonstrates the feasibility of sEMG-based alaryngeal speech recognition, using tailored sensor placement and a personalized wearable device. Further refinement of this approach could allow translation of silently articulated speech into a synthesized voiced speech via portable devices.

Background/Aim: The purpose of this study was to provide preliminary data concerning the effect of clear speech (CS) on Cantonese alaryngeal speakers’ intelligibility. Methods: Voice recordings of 11 sentences randomly selected from the Cantonese Sentence Intelligibility Test (CSIT) were obtained from 31 alaryngeal speakers (9 electrolarynx [EL] users, 10 esophageal speakers and 12 tracheoesophageal [TE] speakers) in habitual speech (HS) and CS. Two naïve listeners orthographically transcribed a total of 1,364 sentences. Results: Significant effects of speaking condition on speaking rate and CSIT scores were observed, but no significant effect of alaryngeal communication methods was noted. CS was significantly slower than HS by 0.78 syllables/s. Esophageal speakers demonstrated the slowest speech rate when using CS, while EL users demonstrated the largest decrease in speaking rate when using CS compared to HS. TE speakers had the highest CSIT scores in HS (listener 1 = 81.4%; listener 2 = 81.3%), and esophageal speakers had the highest CSIT scores in CS (listener 1 = 87.5%; listener 2 = 89.7%). EL users experienced the largest increase in intelligibility while using CS compared to HS (9.1%) followed by esophageal speakers (8.9%) and TE speakers (1.4%). Conclusion: Preliminary data indicate that CS may significantly affect Cantonese alaryngeal speakers’ speaking rate and intelligibility. However, intelligibility appeared to vary considerably across speakers. Further research involving larger, heterogeneous groups of speakers and listeners alongside longer and more refined CS training protocols should be conducted to confirm that CS can improve Cantonese alaryngeal speakers’ intelligibility.

Voice is one of the essential mechanisms for communicating and expressing one’s intentions as a human being. There are several causes of voice inability, including disease, accident, vocal abuse, medical surgery, ageing, and environmental pollution, and the risk of voice loss continues to increase. Novel approaches should have been developed for speech recognition and production because that would seriously undermine the quality of life and sometimes leads to isolation from society. In this review, we survey mouth interface technologies which are mouth-mounted devices for speech recognition, production, and volitional control, and the corresponding research to develop artificial mouth technologies based on various sensors, including electromyography (EMG), electroencephalography (EEG), electropalatography (EPG), electromagnetic articulography (EMA), permanent magnet articulography (PMA), gyros, images and 3-axial magnetic sensors, especially with deep learning techniques. We especially research various deep learning technologies related to voice recognition, including visual speech recognition, silent speech interface, and analyze its flow, and systematize them into a taxonomy. Finally, we discuss methods to solve the communication problems of people with disabilities in speaking and future research with respect to deep learning components.

Purpose The purpose of this study was to report the variability of electrolarynx (EL) users' speech intelligibility in quiet and in multitalker babble. Method Ten EL users (five Servox® Digital, five TruTone™) who were at least 2 years postlaryngectomy provided recordings of five sentences from the 1965 Revised List of Phonetically Balanced Sentences. Recordings were judged by two groups of naïve listeners in quiet and in the presence of multitalker babble. Fifteen listeners orthographically transcribed a total of 750 sentences containing 3,750 key words in quiet, and another 15 listeners orthographically transcribed the same sentences mixed with multitalker babble. Results Significant differences in speech intelligibility were observed between listening conditions; 17.9% more key words were correctly identified in quiet compared to multitalker babble. Significant differences in fundamental frequency (F 0 ) standard deviation and range but not speech intelligibility were observed between EL device types. A positive correlation of moderate significance was observed between F 0 standard deviation and intelligibility for TruTone users in multitalker babble. Conclusions Findings suggest that listeners are able to identify a significantly higher percentage of EL users' speech in quiet compared to multitalker babble, but a large variability in EL users' speech intelligibility exists. Continued investigation involving a larger number of EL users is necessary to confirm this study's findings. Future research should explore the relationships among F 0 measures, speaker characteristics (e.g., rate of speech, articulatory precision), and speech intelligibility, in addition to improving alaryngeal rehabilitation training protocols for EL users.

Introduction The impact of advanced laryngeal cancer and its extensive surgical treatments cause significant morbidity for these patients. Total laryngectomy impacts essential functions such as breathing, communication and swallowing, and may influence the quality of life as well as affecting the social life of laryngeal cancer patients. Objective Describe the quality of life and analyze the factors associated with the reduced quality of life in patients who have undergone total laryngectomy. Method Observational cross-sectional study was carried out to evaluate the quality of life of patients who had undergone total laryngectomy due to laryngeal cancer. The fourth version of the UW-QOL Quality of Life Assessment Questionnaire from Washington University, validated for Portuguese, was used. Results The study population was 95 patients, and the mean composite score of the QOL was 80.4. In the subjective domains the majority of the patients (38.9%) reported they felt much better at present compared to the month before being diagnosed with cancer. When questioned about how they evaluated their health-related quality of life, there was a predominance of those who considered it good (43.2%), and most considered they had a good quality of life (46.3%) considering personal well-being. The overall quality of life was considered good to excellent by 83.2% of the patients. Patients with tracheoesophageal prosthesis reported a better quality of life, compared to patients using an electrolarynx or esophageal voice. Conclusion The high mean value of the composite score for quality of life revealed that the patients assessed their quality of life positively. The absence of vocal emission was the only variable associated with a lower quality of life within the composite score according to the UW-QOL questionnaire.

PurposeTo assess feasibility of producing intelligible and comprehensible speech with an electrolarynx; measure anxiety, communication ease, and satisfaction before/after electrolarynx training; and identify barriers/facilitators.MethodsWe included tracheostomized adults from 3 units following commands, reading English, and mouthing words. On enrolment, we measured anxiety, ease, and satisfaction with communication. We gave electrolarynx instruction for ≤5 days then 2 independent raters assessed intelligibility, sentence comprehensibility (9-point difficulty scale), and Electrolarynx Effectiveness Score (EES), and re-evaluated anxiety, communication ease, and satisfaction. Interviews explored barriers/facilitators.Measurements and main resultsWe recruited 24 participants (Jan2015-Dec2016). Mean (SD) intelligibility was 45%(18%) words correct: 57%(21%) when facing. Mean comprehension difficulty was 6.4(2.0) overall, indicating moderate difficulty (5.5(2.5) scored visualizing). Mean EES was 2.9(1.0) (3 = improved lip-reading through recognizable sounds). Anxiety decreased from median 3.8 to 2.0 (P = .007). Communication was rated easier (median 15 vs 12, P = .04) whereas satisfaction remained similar (P = .06). Facilitators included device friendliness, patient independence, and word intelligibility. Barriers were patient weakness, difficulty positioning the device, and limited sentence as opposed to word intelligibility.ConclusionThe electrolarynx may aid intelligible speech for some tracheostomized patients if the communication partner can visualize the users face, and reduce anxiety and make patient perceived communication easier.

Purpose To determine the influence of clear speech on auditory-perceptual judgments of speech acceptability and listener comfort for electrolaryngeal speech. Method Voice recordings were obtained from 10 electrolaryngeal speakers. Each speaker read the Rainbow Passage in two conditions: habitual speech and clear speech. Speakers were encouraged to speak as clearly as possible and over-articulate in the clear speech condition. Auditory-perceptual rating tasks were completed by 20 normal-hearing adults who evaluated 20 randomized voice recordings. Two counterbalanced listening sessions were used to gather ratings of speech acceptability and listener comfort. Results A significant effect of speaking condition was found on listener judgments of speech acceptability, but not listener comfort. However, listener scores for speech acceptability and listener comfort were found to be significantly related. For all speakers, objective temporal measures indicated reduced speaking rates in the clear speech condition. Conclusions These findings suggest that volitional attempts to improve electrolaryngeal speech using clear speech might negatively impact listener judgments of speech acceptability, but not listener comfort. Further, the data suggest that speech acceptability and listener comfort might address unique perceptual entities. Overall, the strong relationship between these auditory-perceptual dimensions provide support for the use of scaled measurements to assess the impact of speech rehabilitation on individuals who use the electrolarynx.

Purpose Perceived listening effort is a perceptual dimension used to identify the amount of work necessary to understand disordered speech. The purpose of this study was to investigate the utility of perceived listening effort to provide unique information about disordered speech. The relationships between perceived listening effort and two current outcome measures (speech acceptability, intelligibility) were examined for listeners rating electrolaryngeal speech, along with their reliability and intra-rater agreement. Methods Ten healthy male speakers read low-context sentences using an electrolarynx. Twenty-five inexperienced listeners orthographically transcribed and rated the stimuli for perceived listening effort and speech acceptability using a visual analog scale. Strict reliability and agreement criteria were set. Results Perceived listening effort was moderately to strongly correlated with intelligibility (r = −0.76) and acceptability (r = −0.80), each of which contributed uniquely to ratings of perceived listening effort. However, only 17 listeners met stringent reliability and agreement criteria. Conclusions Ratings of perceived listening effort may provide unique information about the communicative success of individuals with communication disorders. There is great variability, however, among inexperienced listeners’ perceptual ratings of electrolaryngeal speech. Future research should investigate variables that may affect perceived listening effort specifically and auditory-perceptual ratings in general.

Background Esophageal speech (ES), tracheoesophageal speech (TES) and/or electrolarynx speech (ELS) are three speech rehabilitation methods which are commonly provided after total laryngectomy (TL). Methods A systematic review of the literature was conducted to evaluate comparative acoustic, perceptual, and patient-reported outcomes for ES, TES, ELS and healthy speakers. Results Twenty-six articles could be included. In most studies, methodological quality was low. It is likely that an inclusion bias exists, many studies only included exceptional speakers. Significant better outcomes are reported for TES compared to ES for the acoustic parameters, fundamental frequency, maximum phonation time and intensity. Perceptually, TES is rated with a significant better voice quality and intelligibility than ES and ELS. None of the speech rehabilitation groups reported clearly better outcomes in patient-reported outcomes. Conclusions Studies on speech outcomes after TL are flawed in design and represent weak levels of evidence. There is an urge for standardized measurement tools for evaluations of substitute voice speakers. TES is the favorable speech rehabilitation method according to acoustic and perceptual outcomes. All speaker groups after TL report a degree of voice handicap. Knowledge of caretakers and differences in health care and insurance systems play a role in the speech rehabilitation options that can be offered. Electronic supplementary material The online version of this article (doi:10.1007/s00405-017-4790-6) contains supplementary material, which is available to authorized users.

Dear Editor, The management of laryngeal cancer is focused on improvingsurvival while preserving function; nevertheless, total laryngectomy is often required for primary and recurrent disease. While total laryngectomy is undoubtedly an effective oncologicalsurgery, it profoundly alters speech, respiration and sense of smell and taste. Specifically, the loss of voicehas the impact on the psychosocial and economic consequencesfollowing laryngectomy.There are three methods of voice rehabilitation after totallaryngectomy: electrolarynx, oesophageal speech andtracheo-oesophageal (TE) speech. Historically, oesophagealspeech was the method of choice by which all otherswere compared, and patients who could not master oesophagealspeech used the electrolarynx. In 1969, Staffieri introduced a surgical voice restoration techniquecalled “phonatory neoglottis surgery”: this was a personaltechnique that allowed one-way air transit from the lungsto the hypopharynx or oesophagus through a fistula betweenthe trachea and the hypopharynx or oesophagus.In 1977, Amatsu with a different surgical technique thatincluded a posterior tracheal wall flap, namely the “Amatsutracheo-oesophageal shunt”, achieved similar results.Both authors addressed the issue of frequently occurringaspiration and the use of a trachea-oesophageal prosthesisplacement to manage failures. In 1972, Mozolewski firstdescribed a TE shunt prosthesis with a valve function. In1980, Singer and Blom proposed a simplified endoscopicmethod for voice restoration. They addressed the problemsof aspiration and stenosis (of the fistula) by meansof a valved prostheses placed inside the TE fistula. Thisprocedure was initially proposed as a secondary salvagetechnique for patients who failed oesophageal speech orthose who were displeased with the electrolarynx voice.Maves and Lingeman and Hamaker et al. were the firstto introduce TE puncture with voice prosthesis as a primarytechnique, performed at the time of laryngectomy.Nowadays, TEP with voice prosthesis is the gold standardfor voice rehabilitation after total laryngectomy.

An electrolarynx (EL) is one of the most popular voice rehabilitation technologies used after laryngectomy. However, most ELs generate monotonic EL speech, which has been shown to create a particular deficit in speech intelligibility, especially for Chinese Mandarin (Mandarin). Mandarin is a tonal language that makes lexical distinctions using variations in tone. Our purpose is to design an EL that can produce the four Mandarin tones, and to evaluate its performance. We designed a fundamental frequency (F0) control method for Mandarin EL speech and manufactured a touch-controlled electrolarynx (T-EL) prototype. Using monosyllables, disyllabic words, and frequently used phrases, we evaluated speech produced with a T-EL, as well as with monotone (M-EL) and variable-frequency modes (P-EL) of a commercially available TruTone EL. A male native Mandarin speaker with laryngectomy volunteered to be the speaker. Results show that the normal speech pitch contours of the four Mandarin tones were most closely matched by the characteristics produced with T-EL. The statistical accuracy of the T-EL’s tone and word perception was significantly higher than that of the other EL types. Moreover, the confusion matrix indicates that the listeners could correctly identify the tones of monosyllables and disyllabic words in T-EL speech. Accurate tone judgment can improve the intelligibility of EL speech in Mandarin. The mean opinion score was used to evaluate the listeners’ acceptability of EL speech. The scores of the T-EL and M-EL were very close, and the score of the P-EL was significantly lower than that of the other two ELs. However, the results from a single speaker cannot provide sufficient data to conclude which EL has a higher acceptability. The evaluation of multiple EL speakers with different EL types at difference levels of proficiency should be studied in future research.

Purpose The purpose of this study was to determine listeners' ability to learn talker identity from speech produced with an electrolarynx, explore source and filter differentiation in talker identification, and describe acoustic-phonetic changes associated with electrolarynx use. Method Healthy adult control listeners learned to identify talkers from speech recordings produced using talkers' normal laryngeal vocal source or an electrolarynx. Listeners' abilities to identify talkers from the trained vocal source (Experiment 1) and generalize this knowledge to the untrained source (Experiment 2) were assessed. Acoustic-phonetic measurements of spectral differences between source mechanisms were performed. Additional listeners attempted to match recordings from different source mechanisms to a single talker (Experiment 3). Results Listeners successfully learned talker identity from electrolarynx speech but less accurately than from laryngeal speech. Listeners were unable to generalize talker identity to the untrained source mechanism. Electrolarynx use resulted in vowels with higher F1 frequencies compared with laryngeal speech. Listeners matched recordings from different sources to a single talker better than chance. Conclusions Electrolarynx speech, although lacking individual differences in voice quality, nevertheless conveys sufficient indexical information related to the vocal filter and articulation for listeners to identify individual talkers. Psychologically, perception of talker identity arises from a “gestalt” of the vocal source and filter.

Understanding the sound transmission of the neck tissue is necessary and important in areas such as vocal function evaluation and electrolarynx improvement. In this paper, a simple method using a reflectionless tube was proposed to measure the neck frequency response function (NFRF) of ten normal subjects (five males and five females) during Mandarin vowel production. The NFRFs across different subjects producing different vowels were measured at different neck positions and compared to confirm the effectiveness of the method, and determine the NFRF variations in normal subjects. The results showed that the proposed method offered an easy and effective way to obtain an accurate NFRF. For normal subjects, the neck tissue can be treated as a low-pass filter, with a maximum gain at 310 Hz and a roll-off at a slope of -8.4 dB/octave, flattening out above 2000 Hz. The measurement position on the neck did not influence the shape of the NFRF, but did change the overall gains of the NFRF. In addition, there was a significant gender difference in NFRFs at the low frequencies. Finally, some potential applications of this method and the results are suggested.

To investigate voice-related quality of life in an effort to index self-assessed voice disability in speakers who use the electrolarynx and to determine the perceived level of influence of the electrolarynx on vocal communication.Prospective study.This study was conducted at a tertiary care facility.Forty laryngectomized adults (25 men, 15 women) who used the electrolarynx as a primary method of communication served as participants. The Voice-Related Quality of Life measure was administered and scored in standard fashion and descriptive data generated for physical, social-emotional, and total scores.Data indicate substantial variability in self-perceived quality of life specific to voice use; a wide range of physical, social-emotional, and total scores were observed. Only one-quarter of these participants rated themselves as having "poor/fair" voice-related quality of life.Our findings suggest that use of the electrolarynx as a postlaryngectomy method of verbal communication has a wide-ranging influence on self-perceived voice-related quality of life and that mean scores from prior studies may not accurately reflect the potential value of the electrolarynx. Communication disability related to electrolarynx use does in fact vary; however, it is not uniformly poor, and some may be highly proficient users. Consequently, the Voice-Related Quality of Life measure may also serve as a useful tool for clinical documentation of rehabilitation outcomes in those who use the electrolarynx as a postlaryngectomy method of speech.

Larynx has a complex structure with joints and multiple functions. In order to study the artificial larynx and artificial auricle scaffold, a three-dimensional digital model of laryngeal joint is established in this paper using MIMICS with its biomechanical properties analyzed and calculated by using the finite element method. This model is based on the CT scanned images of 281 layers with an interlamellar spacing of 1.25 mm. The obtained data are denoised, segmented and smoothed before being loaded into MIMICS. By further optimizations, an accurate and complete 3D model can be obtained. Subsequently, a 3D FEM of the normal larynx joint is performed which allows observations from any dimensions and angles. Compared with natural laryngeal joint, this model has good geometric similarity and mechanically similar throat voicing functions.

Electrolarynx (EL) is a medical speech-recovery device designed for patients who have lost their original voice box due to laryngeal cancer. As a substitute for human larynx, the current commercial EL voice source cannot reconstruct natural EL speech under laryngectomy conditions. To eliminate the abnormal acoustic properties of EL speech, a supraglottal voice source with compensation of vocal tract characteristics was proposed and provided through an experimental EL(SGVS-EL) system. The acoustic analyses of simulated EL speech and reconstructed EL speech produced with different voice sources were performed in the normal subject and laryngectomee. The results indicated that the supraglottal voice source was successful in improving the acoustic properties of EL speech by enhancing low- frequency energy, correcting the shifted formants to normal range, and eliminating the visible spectral zeros. Both normal subject and laryngectomee also produced more natural vowels using SGVS-EL than commercial EL, even if the vocal tract parameter was substituted and the supraglottal voice source was biased to a certain degree. Therefore, supraglottal voice source is a feasible and effective approach to improving the acoustic quality of EL speech.

Tone is important in tonal languages, especially in Mandarin. However, there is presently no commercially available electrolarynx (EL) for laryngectomized Mandarin speakers. Moreover, few studies have focused on this area. Our purpose is to design an EL that produces the four Mandarin tones and to evaluate its performance. We designed a wheel-controlled pitch-adjustable EL and manufactured a prototype (Wheel-EL). Using monosyllables, disyllabic segments, and frequently used phrases, we evaluated speech produced by Wheel-EL and by monotone (M-TruTone) and variable-frequency modes (V-TruTone) of the commercially available TruTone EL. The pitch contours of the high-level (HL), middle-rising (MR), and falling-rising (FR) tones produced by Wheel-EL most closely matched the natural speech characteristics of a native speaker. However, redundant sounds were generated in the high-falling (HF) tone. The statistical accuracy of Wheel-EL’s tone and word perception was significantly higher than that of other EL types. However, no significant differences existed in acceptability among the three EL speech types. Wheel-EL produces better HL, MR, and FR tones in Mandarin than either M-TruTone or V-TruTone. Nevertheless, redundant sounds affect HF phonation. Accurate tone judgment can improve the intelligibility of EL speech in Mandarin but has no obvious effect on acceptability.

This study investigated the relationship between psychological well-being and different voice rehabilitation methods in total laryngectomy patients. The study enrolled 96 patients who underwent total laryngectomy. The patients were divided into three groups according to the voice rehabilitation method used: esophageal speech (24 patients); a tracheoesophageal fistula and Provox 2 voice prosthesis (57 patients); or an electrolarynx (15 patients). The participants were asked to complete the Turkish version of the Voice Handicap Index-10 (VHI-10) to assess voice problems. They were also asked to complete the Turkish version of the Perceived Stress Scale (PSS), and the Hospital Anxiety and Depression Scale (HADS). The test scores of the three groups were compared statistically. Patients who used esophageal speech had a mean VHI-10 score of 10.25 ± 3.22 versus 19.42 ± 5.56 and 17.60 ± 1.92 for the tracheoesophageal fistula and Provox 2 and electrolarynx groups respectively, reflecting better perception of their voice. They also had a PSS score of 11.38 ± 3.92, indicating that they felt less stressed in comparison with the tracheoesophageal fistula and Provox 2 and electrolarynx groups, which scored 18.84 ± 5.50 and 16.20 ± 3.49 respectively. The HADS scores of the groups were not different, indicating that the patients’ anxiety and depression status did not vary. Patients who used esophageal speech perceived less stress and were less handicapped by their voice.

Purpose To determine (a) the effect of fundamental frequency (f 0 ) on speech intelligibility, acceptability, and perceived gender in electrolaryngeal (EL) speakers, and (b) the effect of known gender on speech acceptability in EL speakers. Method A 2-part study was conducted. In Part 1, 34 healthy adults provided speech recordings using electrolarynges set at 75 Hz, 130 Hz, and 175 Hz, and 36 listeners transcribed the recordings. In Part 2, 22 speech samples were presented to 16 listeners. First, listeners identified the gender of each speaker and judged his or her speech acceptability using rating scales. Second, listeners judged the same samples for speech acceptability when gender information was provided. Results In Part 1, speakers were significantly more intelligible when using 75-Hz devices. In Part 2, the f 0 of the speech signal significantly impacted listeners' accuracy in perceiving the speaker’s gender: In gender-incongruent conditions (males using 175-Hz devices, females using 75-Hz devices), listeners were unable to identify female speakers. Speech acceptability judgments were directly related to intelligibility. Finally, listeners differentially penalized female speakers who used 75-Hz devices when gender information was known. Conclusion Low f 0 facilitated speech intelligibility. However, at low f 0 , listeners were unable to identify females as female, and females were differentially penalized for speech acceptability. Results may have implications for rehabilitation.

Objective: To improve the speech quality of laryngectomized speakers of Mandarin, we designed an electrolarynx with tonal control function (tone-EL) by using the movement of a trackball. The performance of the tone-EL in producing Mandarin was evaluated. Methods: The performance of tone-EL was evaluated via a listening experiment. The perceptual accuracies of monosyllabic words, different categories of phrases with different cues were measured and compared with that produced with a conventional EL. The acceptability of sentences was also measured. Results: The perceptual accuracies of monosyllabic words and tones associated with the words produced with the tone-EL were significantly higher than those of monotonic EL speech. The perceptual accuracy of phrases was significantly higher than in monotonic EL speech when no categorical cue for listeners was provided, whereas they were at a close level when categorical information of the phrases was provided in advance. The acceptability of sentences was higher than that of monotonic EL speech. Conclusion: Using the tone-EL can produce Mandarin tones effectively and the quality of rehabilitated Mandarin is better than using a conventional-EL. To balance speech intelligibility and ease of use, a strategy -producing tonal speech when few informative cues are available to listeners is preferred.

The objective of this study was to determine if the design enhancements incorporated into the new Provox Vega Indwelling Voice prostheses result in any positive benefits in vivo.Using a randomized, crossover study design, 31 participants using tracheoesophageal speech postlaryngectomy completed a 3-week trial of the Provox Vega and a comparator device. Main outcome measures included patient perceptions of vocal effort and quality using each device, and perceptual judgments of voice quality produced.The majority of patients (72%) indicated the Provox Vega gave them overall better voice quality and 52% felt they required less effort to phonate. Voice samples produced with the Provox Vega were also perceived by listeners to be significantly (p.05) less strained, easier to understand, produced with less effort, and the better speech sample overall.Results support that the aerodynamic improvements incorporated in the design of the new Provox Vega facilitate enhanced voice and speech qualities.

Objective In Hong Kong, esophageal (SE), tracheoesophageal (TE), electrolaryngeal (EL), and pneumatic artificial laryngeal (PA) speech are commonly used by laryngectomees as a means to regain verbal communication after total laryngectomy. While SE and TE speech has been studied to some extent, little is known regarding the EL and PA sound quality. The present study examined the sound quality associated with SE, TE, EL, and PA speech, and compared with that associated with laryngeal (NL) speech by using long-term average speech spectra (LTAS). Methods Continuous speech samples of reading a 136-word passage were obtained from NL, SE, TE, EL, and PA speakers of Cantonese. The alaryngeal speakers were all superior speakers selected from the New Voice Club of Hong Kong, which is a self-help organization for the laryngectomees in Hong Kong. TE speakers were fitted with Provox valve, and EL speakers used Servox-type electrolarynx. Speech samples were digitized at 20 kHz and 16 bits/sample by using Praat, based on which LTAS contours were developed. First spectral peak (FSP), mean spectral energy (MSE), and spectral tilt (ST) derived from the LTAS contours associated with different speaker groups were compared. Results Data revealed all speakers generally exhibited similar LTA contours. However, PA speakers exhibited the lowest average FSP value and the greatest average MSE value. NL phonation was associated with a significantly greater ST value than alaryngeal speech of Cantonese. Conclusion The differences in FSP, MSE, and ST values in different speaker groups may be related to the different sound sources being used by the laryngectomees, and the difference in the way the sound source is coupled with the vocal tract system.

The goal of this randomized controlled study was to investigate the effect of Heat and Moisture Exchanger use on pulmonary symptoms and quality of life aspects in laryngectomized patients. Eighty laryngectomized patients were included and randomized into an HME and Control group. The effect of the HME was evaluated by means of Tally Sheets and Structured Questionnaires. The results showed a significant decrease in the frequency of coughing, forced expectoration, and stoma cleaning in the HME group. There were trends for the prosthetic speakers to report more fluent speech with the HME and for the HME group to report fewer sleeping problems. In conclusion, this study, performed in Poland, confirms the results of previous studies performed in other countries, showing that pulmonary symptoms decrease significantly with HME use and that related aspects such as speech and sleeping tend to improve, regardless of country or climate.

Three individuals with total laryngectomy were studied for their ability to control a hands-free electrolarynx (EL) using neck surface electromyography (EMG) for on/off and pitch modulation. The laryngectomy surgery of participants was modified to preserve neck strap musculature for EMG-based EL control (EMG-EL), with muscles on one side maintaining natural innervation and those on the other side receiving a transferred recurrent laryngeal nerve (RLN). EMG from each side of the neck controlled the EMG-EL across a day of unstructured practice followed by a day of formal training, including EMG biofeedback. Using either control source, participants spoke intelligibly and fluently with the EMG-EL before formal training. This good initial performance did not consistently improve across testing for either control source in terms of voice timing, speech intelligibility, fluency, and intonation of interrogative versus declarative sentences. Neck strap muscles have activation patterns capable of simple alaryngeal voice control without requiring RLN transfer. Learning outcomes: The reader will better understand (1) functionality of the hands-free electrolarynx (2) modification of laryngectomy surgery to preserve neck strap musculature and (3) performance of hands-free electrolarynx with different control sources.

In normal speech, coordinated activities of intrinsic laryngeal muscles suspend a glottal sound at utterance of voiceless consonants, automatically realizing a voicing control. In electrolaryngeal speech, however, the lack of voicing control is one of the causes of unclear voice, voiceless consonants tending to be misheard as the corresponding voiced consonants. In the present work, we developed an intra-oral vibrator with an intra-oral pressure sensor that detected utterance of voiceless phonemes during the intra-oral electrolaryngeal speech, and demonstrated that an intra-oral pressure-based voicing control could improve the intelligibility of the speech. The test voices were obtained from one electrolaryngeal speaker and one normal speaker. We first investigated on the speech analysis software how a voice onset time (VOT) and first formant (F1) transition of the test consonant-vowel syllables contributed to voiceless/voiced contrasts, and developed an adequate voicing control strategy. We then compared the intelligibility of consonant-vowel syllables among the intra-oral electrolaryngeal speech with and without online voicing control. The increase of intra-oral pressure, typically with a peak ranging from 10 to 50 gf/cm2, could reliably identify utterance of voiceless consonants. The speech analysis and intelligibility test then demonstrated that a short VOT caused the misidentification of the voiced consonants due to a clear F1 transition. Finally, taking these results together, the online voicing control, which suspended the prosthetic tone while the intra-oral pressure exceeded 2.5 gf/cm2 and during the 35 milliseconds that followed, proved efficient to improve the voiceless/voiced contrast.

Objective: Patients of laryngeal cancer who have undergone the surgical removal of the entire larynx suffer the loss of phonation. Electrolarynx (EL) speech is the most commonly adopted alaryngeal phonation. However, EL speech is notorious of the sound quality being monotonic and robotic with the lack of pitch control and the presence of the radiated noise. This paper provides a review of modalities in EL speech as well as introducing the technologies to control the pitch and reduce the noise of the device. Methods: Improvements of EL speech quality have been divided into two parts: improving the sound quality of EL device by applying different enhancement algorithms to reduce the radiated and the additive noise, and implementing pitch-control function to the EL with advanced technology. Results: Adaptive filtering and the subtractive-type algorithms have shown to be able to reduce the noise level associated with EL speech. And more mature technologies are showing promise to the making of a hand-free EL system producing more accurate and synchronized pitch and voice onset control. Conclusion: The advent of micro-technology and human-machine integration promisingly improves EL speech quality and more efficient algorithms enhanceEL soundquality. Suchimprovementsapparently improvethe intelligibility of ELspeech, and thusbetter quality oflife of the EL speakers. # 2007 Elsevier Ireland Ltd. All rights reserved.

Three methods of voice restoration--tracheosophageal speech (TEP), oesophageal speech, electrolarynx--are available following total laryngectomy. TEP produces better voice quality compared with other methods and is assumed to result in better quality of life. Little evidence exists to support the relationship between voice quality and quality of life, however. Advertising this study through several leading laryngectomy charities resulted in the completion of 226 questionnaires (TEP = 147; oesophageal speech = 42; electrolarynx = 37) comprising the Short Form 36 (SF-36) quality of life measure and questions examining perceived voice intelligibility. Additionally, 89 questionnaires comprising only the SF-36 were completed by participants who reported having no serious medical problems, to form a healthy control group. Results indicate that improved voice quality does not result in widespread benefits to quality of life. On only a few dimensions were there differences between voice restoration method: electrolarynx and TEP better than oesophageal speech with respect to pain, TEP better than oesophageal speech with respect to role limitation: physical problems. Additionally whilst widespread differences between voice restoration methods did not occur, all three groups had a worse quality of life compared with the healthy control group. Implications of the results for the selection of voice restoration method to maximize quality of life are discussed.

Purpose The electrolarynx (EL) is a widely used device for alaryngeal speech, but it requires manual operation and produces voice that typically has a constant fundamental frequency. An electromyographically controlled EL (EMG-EL) was designed and implemented to provide hands-free control with dynamic pitch modulation. Method Three participants who underwent total laryngectomy surgery and 4 participants with normal voice were trained to produce EMG-EL speech through a multiple-baseline, successive-stage protocol. Baseline performance was established through 3 testing probes, followed by multiple hour-long training sessions. Results At the end of the training, all participants learned to initiate, sustain, and terminate EMG-EL activation in correspondence with articulation, and most were able to modulate the pitch to produce intonational contrasts. After completing the testing/training protocol, 1 of the 3 participants who underwent total laryngectomy was encouraged to independently use the EMG-EL at his residence. This participant sustained his performance for an additional 6 weeks and also used the EMG-EL successfully to communicate over the phone. Conclusions Our findings suggest that some participants with laryngectomies and vocally normal individuals can learn to produce hands-free speech using the EMG-EL device within a few hours and that significant additional gains in device control (particularly pitch modulation) are attainable through subsequent training sessions.

Excellent results have been reported with the use of voice prostheses for the rehabilitation of laryngectomees. Patients, however, consider it a disadvantage that the tracheostoma must be closed manually for speech production. This limits their ability to simultaneously communicate by gesture or to work with both hands. An automatic tracheostoma valve helps patients overcome this problem. We describe a prospective clinical trial evaluating our experience with the Provox FreeHands HME Automatic Tracheostoma Valve® system. Twenty-four laryngectomees were randomly selected from the patients who had undergone laryngectomy at the ENT Department. Immediately, after 4 weeks and 6 months later having been fitted with a Provox FreeHands HME®, the patients were asked to complete a questionnaire in order to assess their satisfaction, voice quality, wearing comfort, fixation, potential problems, and the effectiveness of the HME cassette. In addition, we investigated relevant voice quality parameters including dynamics range, frequency range of the speaking voice, and maximum phonation time. Seven patients discontinued the study due to problems of securing the valve to the skin (four patients) or recurrent cancer (three patients). Ten of the remaining 17 patients wore the valve daily for an average of 8.4 h. A total of 88% of the patients considered it a great advantage to be able to speak without having to use their hands. With the Provox FreeHands HME®, maximum phonation time was 8.7 (±6.2) s and the dynamic range was 21.9 (±5.8) decibels. The results show that the Provox FreeHands HME Automatic Tracheostoma Valve® system not only allows hands-free speech but is also associated with excellent compliance and good voice rehabilitation.

The ability to speak and communicate vocally is a unique human characteristic that is often taken for granted but is fundamental to many activities of daily living. Loss of voice after total laryngectomy can lead to a serious decrease in quality of life and can precipitate significant frustration over the inability to communicate effectively. There are 3 main methods of voice restoration: esophageal speech, usage of the electrolarynx, and tracheal-esophageal puncture for tracheal-esophageal speech, which can be performed primarily or secondarily. Although all 3 methods have potential benefits, the gold standard is tracheal-esophageal speech.

Although electrolarynx (EL) serves as an important method of phonation for the laryngectomees, the resulting speech is of poor intelligibility due to the presence of a steady background noise caused by the instrument, even worse in the case of additive noise. This paper investigates the problem of EL speech enhancement by taking into account the frequency-domain masking properties of the human auditory system. One approach is incorporating an auditory masking threshold (AMT) for parametric adaptation in a subtractive-type enhancement process. The other is the supplementary AMT (SAMT) algorithm, which applies a cross-correlation spectral subtraction (CCSS) approach as a post-processing scheme to enhancing EL speech dealt with the AMT method. The performance of these two algorithms was evaluated as compared to the power spectral subtraction (PSS) algorithm. The best performance of EL speech enhancement was associated with the SAMT algorithm, followed by the AMT algorithm and the PSS algorithm. Acoustic and perceptual analyses indicated that the AMT and SAMT algorithms achieved the better performances of noise reduction and the enhanced EL speech was more pleasant to human listeners as compared to the PSS algorithm.

Tracheoesophageal voice prostheses need to be replaced due to increased airflow resistance or retrograde leakage of fluid into the trachea as a consequence of biofilm formation. Previous in vitro studies show a change of aerodynamic features of biofilm covered voice prostheses after removal of the prostheses out of the patient. To assess these changes in an in situ situation, aerodynamic characteristics were measured within 45 patients at the beginning and at the end of the wearing process of the Provox 2 voice prosthesis. As a consequence, the influence of biofilm formation on aerodynamic characteristics can be evaluated. In the majority of cases, leakage through the prosthesis was the reason for replacement. No differences were found in the total flow, volume range and intratracheal pressure (ITP) of the voice prostheses measured. The airflow resistance of biofilm covered prostheses was significantly reduced compared to new clean prostheses. However, no correlation was found between the extent of biofilm and the different aerodynamic features measured. Biofilm formation on the Provox 2 is responsible for both reduction in airflow resistance and leakage through the prosthesis by deterioration of the silicone rubber material.

Objective: To analyse the cause of failing voice production by a sound-producing voice prosthesis (SPVP).Methods: The functioning of a prototype SPVP is described in a female laryngectomee before and after its sound-producing mechanism was impeded by tracheal phlegm. This assessment included: perceptual voice evaluation of read-aloud prose by an expert listener; inspection of the malfunctioning SPVP; and aero-acoustical in vivo registrations using a computer-based data acquisition system.Results: Sound-producing voice prosthesis speech is higher pitched, stronger, contains less aperiodic noise and requires a lower airflow rate than the patient's regular tracheoesophageal (TE) shunt speech. Tracheal phlegm caused malfunction of the vibrating silicone lip of the SPVP by causing it to stick to its stainless steel container in an opened position, thereby reducing the SPVP to no more than a regular TE shunt valve from a functional point of view. Tracheal phonatory pressure and dynamic vocal intensity range were not affected by the functional status of the SPVP.Conclusions: To exploit the advantages an SPVP could offer female laryngectomees with an atonic or severely hypotonic pharyngoesophageal segment, the sound-producing mechanism of the SPVP needs to be less vulnerable to tracheal phlegm.

Electrolarynx (EL) speech provides a valuable means of verbal communication for the laryngectomees. Yet EL speech tends to be less intelligible speech due to the presence of background noise. This paper addresses the issue of EL speech enhancement. The proposed approach takes into account the frequency-domain masking properties of the human auditory system for a subtractive-type enhancement process. Subtractive-type algorithms can efficiently reduce the radiated noise of EL speech but not to reduce the additive noise from the environment due to the use of fixed subtraction parameters. Considering the particular characteristics of EL speech, a new computationally efficient algorithm based on the perceptual weighting technique is developed to adapt the subtraction parameters. This leads to a significant reduction of the unnatural structure of the residual noise. Acoustic and perceptual experiments confirm that the enhanced EL speech is more pleasant to human listeners and the proposed algorithm results in improved performance over classical subtractive-type algorithms.

This study investigated the relationship among the magnitude of jaw opening, intrinsic fundamental frequency (F0), and glottal parameters in natural speech. Acoustic, jaw opening, and electroglottographic (EGG) signals were simultaneously recorded. The subjects were 10 healthy men with New Zealand English as their native language. Subjects were asked to repeat a standard nonemphasized sentence in which one of the target vowels (/a/, /e/, /i/, /o/, and /u/) was embedded in various contexts. The glottal parameters F0, open quotient (OQ), and speed quotient (SQ) were measured from the EGG signal. Results of a series of one-way repeated-measures analyses of variance (ANOVA) showed a significant vowel effect on the magnitude of jaw opening [F(4, 24) = 25.512, P.001], F0 [F(4, 28) = 45.415, P.001] and speed quotient [F(4, 28) = 5.233, P = .003], but not on the open quotient [F(4, 28) = 0.501, P = .735]. The magnitude of jaw opening was found to be inversely related with F0 (r = -0.624, n = 25, P = .0009). These findings showed that the magnitude of jaw opening was related to F0 and that jaw opening might be a control signal for simulation of long-term F0 variation to achieve a higher degree of naturalness in artificial voice.

We developed and evaluated an intra-oral electrolaryngeal speech aid system for those who could not acquire common alaryngeal speech or for early post-surgery speech rehabilitation. Our system consisted of a denture-base intra-oral vibrator, a wireless miniature fingertip switch and a controller. To produce natural speech, the fingertip switch produced binary commands of voicing and accent and the controller implemented the pitch generation model using the commands. We first estimated the intelligibility of consonant–vowel syllables produced by our system. We then obtained the feedback about the system from the Japanese users on the basis of their daily life use, and evaluated the possibility and acceptability as an alaryngeal speech aid. Although the users were less satisfied at the intra-oral electrolarynx, the intelligibility of the intra-oral electrolarygeal speech was comparable to that of transcervical electrolaryngeal speech, and most of them were willing to employ it if they lost their current electrolaryngeal speech. According to the feedbacks from the users, a completely wire-free system and less eye-catching designs would make the prosthesis more acceptable. These results placed the intra-oral electrolarynx as a useful option of alaryngeal speech aids and encouraged the further development of the intra-oral electrolarynx.

The new Provox NID non-indwelling voice prosthesis investigated in this study provides a good option for laryngectomized patients using non-indwelling voice prostheses and can potentially improve safety and increase patients' satisfaction with their voice and speech.To investigate the feasibility of and patient satisfaction with the Provox NID non-indwelling voice prosthesis.Pre- and post-study questionnaires were used to evaluate the patients' former voice prosthesis and the Provox NID voice prosthesis. In addition, measurements of pull-out force, maximum phonation time and loudness were made for both voice prostheses. In vitro measurements of airflow characteristics were also made. Following a 6-week trial, all patients provided feedback on the new voice prosthesis and the results were used to further improve the Provox NID. This final version of the new voice prosthesis was subsequently trialled and evaluated by 10 patients 6 months later.Overall results showed that patient satisfaction with the Provox NID non-indwelling voice prosthesis was favourable. The pull-out force for the new prosthesis was significantly higher than that for the formerly used prosthesis and its aerodynamic characteristics were better.

This clinical report describes the clinical requirements, treatment sequence, and use of a relatively new intraoral electrolarynx for a completely edentulous patient. This device consists of a sound source attached to the maxilla and a hand-held controller unit that controls the pitch and volume of the intraoral sound source via transmitted radio waves.

Since the first reports of laryngectomy surgery, voice preservation has been an important consideration in planning treatment and developing improved methods. General acceptance of laryngectomy for the management of laryngeal cancer demands a realistic chance of voice preservation. The most frequently quoted paper describing the first successful laryngectomy reported Billroth’s operation and proposed a fistula technique for voice restoration [1]. The procedure used a pharyngostoma to manage secretions and an external device to direct exhaled air into the pharynx for voice production. By the late 19th century, the pharyngostoma was no longer part of the laryngectomy procedure, making it more acceptable, but voice rehabilitation required the development of esophageal speech or an external device to provide vibrating air for phonation. A number of pneumatic or electrical devices became available for voice. The most effective was esophageal speech, which freed the laryngectomee from devices and provided an ‘‘internal’’ voice from the patient’s natural pharyngoesophageal tissues, often called the pseudoglottis. The acquisition of esophageal speech requires dedicated training, and depends on the development of the pseudoglottis after laryngectomy, which is never a planned part of the procedure. For these reasons, less than one third of laryngectomees acquire esophageal speech, and only a few are considered exceptional speakers. Thus, many patients are relegated to unnaturalsounding external devices, writing pads, or silence. Alternatively, with the development of clinical radiation therapy techniques, treatment of many laryngeal cancers by a nonsurgical method is more acceptable to patients and medical colleagues. This preference for nonsurgical management of laryngeal cancer is the basis for today’s organ-preservation protocols. The recurring and

Measurements of the neck frequency response function (NFRF), defined as the ratio of the spectrum of the estimated volume velocity that excites the vocal tract to the spectrum of the acceleration delivered to the neck wall, were made at three different positions on the necks of nine laryngectomized subjects (five males and four females) and four normal laryngeal speakers (two males and two females). A minishaker driven by broadband noise provided excitation to the necks of subjects as they configured their vocal tracts to mimic the production of the vowels /a/, /ae/, and /I/. The sound pressure at the lips was measured with a microphone and an impedance head mounted on the shaker measured the acceleration. The neck wall passed low-frequency sound energy better than high-frequency sound energy, and thus the NFRF was accurately modeled as a low-pass filter. The NFRFs of the different subject groups (female laryngeal, male laryngeal speakers, laryngectomized males, and laryngectomized females) differed from each other in terms of corner frequency and gain, with both types of male subjects presenting NFRFs with larger overall gains. In addition, there was a notable amount of intersubject variability within groups. Because the NFRF is an estimate of how sound energy passes through the neck wall, these results should aid in the design of improved neck-type electrolarynx devices.

To report on the long-term results, focusing on prosthesis lifetime, achieved with the VoiceMaster prosthesis in an outpatient population.The VoiceMaster prosthesis was used over a 40-month period. Average prosthesis lifetimes were calculated both individually and for the group as a whole. Factors determining prosthesis insertion were noted. Also, the possible effect of interim prosthesis cleaning and reinsertion of the same device, a specific VoiceMaster characteristic, was assessed.An average prosthesis lifetime of 6.5 months was attained for the whole patient group and several devices were still in situ at the end of the 40-month period. Local factors (tracheostoma size, fistula position and characteristics) influence insertion. Interim cleaning with immediate reinsertion of the device can greatly enhance prosthesis lifetime on an individual basis.The attained average prosthesis lifetime demonstrates that the VoiceMaster merits a place within the array of available prostheses used in post-laryngectomy outpatient voice rehabilitation.